That doesn't make much sense. The rimless case headpaces off the shoulder, at the "datum line", the rimmed version off the rim. The lengths of the two cartridges from the rim to the shoulder "datum line" would have to be exactly the same, or there indeed would be problems with excess hedspace. A full length sizing die can quite easily cause problems in this regard. It could, of course, be made to work, but I would think just substituting rounds "right out of the box" your chances might not be too good. You might well say you have done it and it worked, but that would be a fluke I think.
